The present invention relates to computer animation. More specifically, the present invention relates to management of animation objects.
Throughout the years, movie makers have often tried to tell stories involving make-believe creatures, far away places, and fantastic things. To do so, they have often relied on animation techniques to bring the make-believe to “life.” Two of the major paths in animation have traditionally included, drawing-based animation techniques and stop motion animation techniques.
Drawing-based animation techniques were refined in the twentieth century, by movie makers such as Walt Disney and used in movies such as “Snow White and the Seven Dwarves” and “Fantasia” (1940). This animation technique typically required artists to hand-draw (or paint) animated images onto a transparent media or cels. After painting, each cel would then be captured or recorded onto film as one or more frames in a movie.
Stop motion-based animation techniques typically required the construction of miniature sets, props, and characters. The filmmakers would construct the sets, add props, and position the miniature characters in a pose. After the animator was happy with how everything was arranged, one or more frames of film would be taken of that specific arrangement. Stop motion animation techniques were developed by movie makers such as Willis O'Brien for movies such as “King Kong” (1932). Subsequently, these techniques were refined by animators such as Ray Harryhausen for movies including “The Mighty Joe Young” (1948) and Clash Of The Titans (1981).
With the wide-spread availability of computers in the later part of the twentieth century, animators began to rely upon computers to assist in the animation process. This included using computers to facilitate drawing-based animation, for example, by painting images, by generating in-between images (“tweening”), and the like. This also included using computers to augment stop motion animation techniques. For example, physical models could be represented by virtual models in computer memory, and manipulated.
One of the pioneering companies in the computer aided animation (CAA) industry was Pixar, dba Pixar Animation Studios. Over the years, Pixar developed and offered both computing platforms specially designed for CAA, and rendering software now known as RenderMan®. RenderMan® renders images based upon geometric scene descriptors including references to object models. Between different scenes, the objects are typically repositioned, or animated by an animator. To specify the animation of the object, the animator uses one or more object rigs to manipulate the object in time.
One method for creating an object is via creating an object from scratch. For example, the user specifies an object from the ground-up. Such a technique is of course inefficient, as often objects have portions that could be reused by other users for other objects or the user could use portions of other users' objects.
One method for creating an object, not necessarily in the prior art, is with the use of templates as starting points for customization. For example, to create an object, a user may retrieve a template for the object, customize it, and then save the customized object. As another example, a user may use templates of more than one object as a starting point to create a larger object, and then customize the objects. In such cases, after customization, the objects that are specified by the templates are stored as part of the created object.
Disadvantages to these approaches include that subsequent changes to the original model template, after the object template was used, are not propagated to the created object. Instead, any changes to the object template would have to be manually propagated to the objects that used the template. Additionally, disadvantages include that users could customize an object so significantly that it would effectively be useless to other users.
The inventors of the present invention have determined that improved methods for crating and updating objects are needed without the drawbacks illustrated above.